Releasing-seal for fire extinguishing chambers



March 1, 1932. ,1. SALMON!) 1,847,628

RELEASING SEAL FOR FIRE EXTINGUISHING CHAMBERS Filed A 17. 1929 INVENTOR (fa/$12 Jalm 0220 BY ATTORNEY.

Patented Mar. 1, 1932 UNITED-j STATES PATENT OFFICE,

JOHN SALMOND, 01 LOS ANGELES, CAL

OF CALIFORNIA; OF LOS AN GELES, CALIFORNIA, A CORPORATION OF CALIFORNIA RELEASING-SEAL FOR FIRE EXTINGUISHING CHAMBERS Application filed August 17, 1929. Serial-1T0. 886,581.

This invention relates to fire extinguishing apparatus for use with oil tanks and more' particularly to a fire extinguishing apparatus by which a plurality of chemical solutions are mixed and introduced onto the surface of the burning oil in the tank to produce a fire extinguishing compound or foam to cover the oil; and has special reference to the provision of eflicient closing or sealing means between the chemical mixing vapparatus and therespective oil tank as well as to a safe and sure means for releasing said sealing or closing means when necessary.

In installations of this type it is customary to deliver two chemical solutions through separate pipes into a conduit or chamber in which the foam is produced, said conduit being installed alongside the oil tank and opening into the same above theoil level. Usually, the discharge opening of the foam conduit or mixing chamber intothe oil tank is left open permitting the volatileand c0rrosive vapors of the oil or other inflammable fluid to enter into the above-mentionedfoam conduit or mixing chamber. Such systems are objectionable since thevapors gradually condense in the mixing chamber, corroding the latter and producing a deposit therein and in the supply pipes, so that the system either becomes clogged with rust, or upon operation discharges such condensed inflammable fluid onthe fire thereby increasing instead of smothering the same. I

An object of the invention is to prevent the volatile and corrosive vapors evolved by the inflammable fluid in the oil tank or other container from entering the above-mentioned foam conduit or mixing chamber, thus keeping the latter free and operative when a fire breaks out in the container.

The invention resides inthe provision of means by which a closure plate istightly held against the opening of the foam conduit into the oil tank, said means being subject to rupture when a pressure substantially greater than atmospheric is created in the foam conduit or mixing chamber, thus permitting the fireextinguishing mixture of foam to be in troduced onto the surface of the oil inthe tank.

The invention further resides in the pro} prevent the closure plate vision ofmeans'to from falling to the bottom of the tank when the rupturable joint is broken, and of means to permit an easy reinstallation and tighten ing of the plate against the discharge opening of the foam conduit after the fire has been extinguished. o

Referring to the drawings which disclose a preferred embodimentof the invention by way of illustration: r

F ig. 1 is an elevation, partially in crosssection, showing a part of an oil tank with a conventional conduit or mixing chamber attached thereto for the introduction of a fire extinguishing compound or foam into said tank, in connection with which the present invention is shown in the form of a closure plateand a rupturable joint normally retain ing the. plate against the discharge end of the conduit to close the latter.

Fig. 2is'an enlarged view of the rupturable joint, the view being partially in elevation and partially in section.

Fig. 3 is an enlarged plan view of the closure-plate; V x

Fig. 4 is an enlarged cross section of a portion of the discharge end of the foam conduit,'and of a portion of the abutting closure plate.

The drawings disclose a conventional container 1 for an inflammable fluid such as oil, the tank bein covered by a top 2 fixed to a rim 3 preferably consisting of an angle iron connected to the top of the tank 1. An opening 4 in the top or roof 2 communicates with a foam conduit or mixing chamber 5, the latter being connected to the top of the tank by means of a flashing 6 and held to the side of the tank 1 by supports 7. Supply pipes 8 and 9 open into the mixing chamber 5 at or near its lower end to deliver the fire extinguishing foam or foam-producing materials thereto.

The releasing seal, which constitutes the present invention, is placed at the discharge end of the foam conduit 5, said release seal consisting of two parts: the closure plate 11 and the rupturable joint 28. Fastened inside the discharge opening of the conduit 5 is a IFORNIA,'AS SIGNOR TO UNION OIL COMPANY flange 10, preferably of light angle iron, against the bottom edge of which seats the closure plate 11 whose upper surface is covered by a gasket 12, spacer strips 13 and 14 having upwardly bent positioning ends being also mounted on the upper surface of said closure plate v11 above the gasket 12. An upwardly extending rod 15, connected to the rupturable joint 28 as described hereinafter and havingan eye 16 at its upper end, is fastened at 17 to the center of the closure plate 11.

An angle iron 18 fixed to the top outside surface of the foam conduit 5 supports a rod 20 by means of a nut 19, said rod 20 having a threaded upper portion 21 receiving the nut. The central portion 22 of the rod is square in cross-section and passes through a square hole 23 in a bracket" 24L fixed onto the top inner surface of the chamber 5. This arrangement prevents the rotation of the rod 20, and therefore of the rupturable joint 28 and of the closure plate 11, when the nut 19 is being turned on the threaded portion 21. The lower end of this rod 20 has an eye 25 similar to the eye 16 on the rod 15.. Placed between the rods 15 and 20 and engaging the eyes 16 and'25 is the rupturable joint comprising two wire clamps 26 and 27 and a short piece of wire 28, said wire clamps holding the wire .28 tightly between their adjacent ends, and the wire being adapted to snap under the pressure developed whenever foam is generated in conduit 5. Flexible means such as a chain 29 connected to the closure plate 11 at 30 and to the foam conduit 5 at 31, permits said closure plate to hang in the tank 1, and manhole cover 32 provided in the foam conduit 5 near the discharge end thereof permits access to the enclosed parts.

The parts of the releasing seal being assembled substantially as described hereinabove and as shown in Figures 1 and 2, the upper end of the rod 20 is tightened against the angle iron 18 by means of the nut 19 so as to hold the closure plate 11 tightly against the rim 1-0 of the foam conduit 5, but was not to break the wire 28 held by the wire clamps 26 and 27 This closes the discharge end of the foam conduit or mixing chamber 5 and prevents the volatile and corrosive vapors in the tank from entering said conduit 5. When a fire starts in the tank 1, the fire extinguishing compounds are introduced through the supply pipes 8 and 9 into the foam generating chamber 5. The pressure which is developed by the pressure generation of the foam is thus applied to the closure plate 11. This pressure becomes sufficiently high to break the wire 28, thereby permitting the closure plate to fall into the tank 1 to the limit of the chain 29 substantially as shown in dotted lines in Fig. 1. Thus liberated, the fire extinguishing foam is free to flow into the tank and onto the surface of the burning fluid to smother the fire.

When the fire has been extinguished, the man-hole 32 is opened, nut 19 on the threaded portion 21 of rod 20 is partially unscrewed, the closure plate 11 is pulled up by means of the chain 29, a new piece of wire 28 is inserted and clamped between the adjacent ends of the clamps 26 and 27, and the nut 19 is again tightened, thus retaining the closure plate .11 in sealing position against the discharge end of the foam conduit 5 to prevent the vapors in the tank from entering said conduit. The man-hole cover 32 is then replaced. It will be observed that the tensioning means, including rod 15, the rupturable links 26, 27 and 28, rod 22 and nut 19, are positioned on the side of the plate 11 nearest the chamber 5, thus permitting of easy accessibility for replacing the ruptured link and tightening the closure plate against its seat at the discharge end of the conduit.

From the foregoing it will'b'e clear that desirable and efiicient means have been presented for closing the discharge end of a foam-generating chamber supplying the fire extinguishing'compound to the tank, said closing means being displaceable by pressure developed when the fire extinguishing compound is injected into said chamber, means being provided to prevent the loss of the closure plate- It should be understood that these disclosures are made merely to illustrate the invention in one operative form and that this invention is to be limited only as defined by the appended claims and is capable of variations within the abilities of those skilled in the art.

I claim:

, 1. In combination a closed tank for volatile fluids, a foam generatingchamber having a discharge conduit discharging into said tank, a closure plate for said discharge con-v duit, a rupturable tension means for holding said plate against said conduit to seal the same, said tensioning means being positioned on the side of the plate nearest the foam generating chamber, means for introducing foam generating chemicals into the foam generating chamber, said tensioning means being adapted to rupture in response to pressure developed by the foam.

2. In combination a closed tank for containing volatile fluids, a foam generating chamber having a discharge conduit discharging into said tank, a closure plate for said discharge conduit, a rupturable tension means for holding said plate against said conduit to seal the same, said tensioning means being positioned on the side of the plate nearest the foam generating chamber, means for introducing foam generating chemicals into the foamgenerating chamber, said tensioning means being adapted to rupture in response to pressure developed by the foam and means for limiting the movement of said plate on rupture of said tension means to prevent the plate falling into said tank.

3. In combination a closed tank for containing Volatile fluids, a foam generating chamber having a discharge conduit discharging into said tank, a closure plate for said discharge conduit, a rupturable tension means for holding said plate against said conduit to seal the same, said rupturable means being positioned exteriorly of said tank, means for introducing foam generating chemicals into the foam generating chamber, said tensioning means being adapted to rupture in response to the pres sure developed by the foam.

4:. In combination a closed tank for containing volatile fluids, a foam generating chamber adapted to discharge into said tank, a closure plate for said chamber, rupturable means positioned Within said chamber to hold said closure plate under tension to close said chamber, means for introducing foam generating chemicals into said foam generating chamber, said tensioning means being adapted to rupture in response to the pressure developed by the foam.

Signed at Wilmington, 0s Angeles, and State of California, this 3 day of August A. D. 1929.

JOHN SALMOND.

in the. county of 

